Crankcase breather hose on AOS end - movable?

Hi! I'm in the process of replacing AOS on 99' Tip (yes... unfortunately...) I have managed to get to the latest step (removed coolant reservoir, fuel filter and bank 1 intake) but looks like that is becoming a major hurdle and possible forces me to start thinking about lowering the engine and transmission. Before that I'm just wondering if that crankcase breathing hose (blue circle) is somehow movable? The issue is that the connector itself in that position is not accessible at all - neither from underside of the car or from the top because it's under and behind those fuel lines. Crankcase breathing hose (blue circle) So I'm playing with an idea that I could loosen the bolts on the AOS and then those hoses on the top and then somehow twist the AOS so that connector becomes more accessible - any idea if that is possible?

I have not attempted the AOS with the engine in the car so others may have differing opinion, however, I would say no. That breather hose goes in at a 90 degree angle as the picture shows and I think as soon as you tried to turn it, you are going to bind the fitting and make it worse. In my case (engine out of the car) the end of that hose broke on me (the connector) as it gets brittle with age. I believe you will do your self a big favor and time saver by lowering the engine to give yourself a little room.

I could reach that connector from the bottom but i have a 6 speed. I was able to unbolt the aos from underneth first, then i pulled the intake to remove it. I did not lower the motor or remove the coolant resi.

I'm with DanielCooper on this one. When I had my engine out of the car and on a stand, when I started to re-assemble it. I got ahead of myself a bit and had everything back on the top of the engine when I realized I forgot that hose I spent close to an hour trying to figure out how to snake it through the intake runners etc. until I finally gave up and started removing the intake system... Do yourself a favor and just bite the bullet...

Thanks - looks like I'm out of other options so dropping the engine + transmission is probably the only option that makes sense - except that I lack the space and knowledge to do that - my garage is too small to move that combo around. I guess dropping the engine just down could be doable with Quickjack and SUV adaptors - or tow it to some shop for fixing this properly. This is so frustrating because the AOS itself is so accessible but those connectors / hoses are the making this nearly impossible. Took a couple of pictures that shows that tight spot - in case someone else finds this useful. I guess this is very engine specific - I have 1999 Carrera 4 with Tiptronic. That crankcase breather hose connector should be pressed from top and bottom and as you can imagine there's no way to press from bottom. Well, if it is somehow possible to squeeze and pull the connector out there's this gasket that will probably drop off somewhere. And not only that but that one vertical pipe blocks also the movement. I wonder how to get that AOS out because the small pipe below that goes into engine has to be moved sideways and that metal pipe blocks that direction because even now it looks like that breather hose is leaning against that pipe so how to move that hose the the left in that picture. Then a smaller but rather crucial thing is also that electrical wire that goes around the AOS. Looks like it's very fragile based on those tiny wires in that connector. Any idea if that could be detached safely? Looks a bit like those other connectors where you can press that metal thing to loose the connector. The wire itself goes quite tightly around the AOS so there's no loose wire that could be routed further way. By the way - any idea where that crankcase breather hose goes to in this engine? Looks like it takes a sharp 180 degree turn and goes behind the engine because it's not coming to the front side from the left side. I tried to trace it with a mirror and a camera (endoscope) and it goes in just under the very last part of that left intake manifold.

I think the Porsche engineer that designed the placement for the M96 AOS deserves a very special place in Hell. I have replaced my AOS in situ and it is one helluva job. Why oh why would some engineer stick a plastic molded rubber diaphragm filled crankcase breather all the way back there? Why not a simple place like where the worthless SAI pump sits? *sighs heavily* I'm feeling for you buddy.......

Dont give up its doable. Put rear of car in jack stands, reach up from the bottom and remove the electrical bracket to access the 2 aos bolts and remove (should be able to do this even with a tip), pull the front and rear crossover plebums, lossen motor mounts and drop motor a few inches with a floor jack(may have to do this step earlier to get to the aos mounting bolts), from top remove the drivers side intake, pull aos. Install uaos upgrade so u never have to do it again. That hose goes to the passenger side to the rear of the motor below the 12v jump point bolt. To replace the tube pull the pass side intake to make it easier. There is also a 90*fitting/valve u should replace too in the pass side.

I had to do this twice in one year and it sucks big time! Mine is a manual so I can't help in regards to a TIP, but if you read through the Ultimate AOS thread there's a lot of good tips in it. Then order the UAOS and geter done!

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Twice... I really can feel the pain you must have felt Were those genuine Porsche parts or some aftermarket part? Thanks - but what to do with that crankcase breather hose connector (the image above shows the issue that I'm having) ? I don't think it will be more accessible if I drop the engine only a few inches - I might be wrong but based on the view from under the car if I drop the engine a few inches it will not help accessing that connector. I think at the moment I can get those two bolts out and the bellows rubber is already cut. If the idea is still to access that from the top I don't think the clearance is an issue - again - might be wrong because this is my first time doing such a thing so it's a bit tricky to estimate the movability of the parts. Here's a bit wider view - there's a few inches of free space on top after I remove the hoses to move the AOS around if the darn crankcase breather hose connector permits.

See my post above. I wrapped some wire around the hose so I could pull it off while pinching the connecter with my other hand. This can also be done on the bottom connection through the wheel well.

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Hmm.. there must be something different between our cars - maybe it's because of the Tip - I can barely reach the rubber bellows let alone the hose connector which is even higher from the wheel well. And then from the top - The pinch points are on the top and bottom - but I can't put my finger to the bottom because there's like a few millimeters of free space - don't know exactly what's there but I can't put my finger under the connector so that I could pinch it properly. Tried to pinch it from the top and help a bit with my other finger from the bottom but wasn't successfull - one of the issue is the pipe just next to the breather hose (check my image above) which basically blocks the movement to the left so that I could pull that connector even if I could somehow pinch it.

Pipe next to the breather hose? You mean the bottom connection or top? Get the coolant line off the top and the fuel rail on the bottom may need to be released. Read through the UAOS thread as others have given tips on removal from a TIP>

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Top - check this - ps. Just reading through the UAOS thread...

Might help to Get the fuel rail out of the way

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Mine is a 2004 MT so it looks a little different, but I would think it goes to the same place. I'm halfway into disassembly for this as well. On mine, that hose comes out of the AOS, but around and over the fuel rail, then through the intake runners (which is it's own problem, I can't get the intake out without disconnecting this hose). But I can follow it. It goes to the passenger rear of the engine. It's held with two bolts on the right rear. Maybe yours takes a different route, but ends up at the same place?

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Once u remove the mounting bolts u can move the aos around and get a better angle in that hose. Just shift and lft it off the motor. That hose is somewhat flexible but becareful and the fitting is a simple tube and oring so it will rotate. Fyi, the 3.4l aos us actually easier the the 3.6. There r differences between the aos mounting and the hoses.

One thing I did was unwrap that stuff on the hoses. Then I could get a slight twist out of the fitting to work it loose. You really have to twist, push and pull to get that hose off the AOS. You have to pinch it right where those ridges are on the fitting. I used this to re-wrap those hoses.

PINCH PUSH THEN PULL.

Quotes source posts: 17018895, 17018703

Yep.... That's one of the reasons why the connector is quite annoying - even though it holds the pipe then properly - as you have to pinch that exactly from the correct point and in correct angle. Uh, one step forward and one step backward. That was sort of my goal. Turns out that one of those pictures is a bit misleading - good news is that there's no pipe behind that 90 angle connector but bad news is that it looks and feels like there one quite stiff but small hose that is attached to the end of one of the fuel lines and continues towards back of the engine. That hose actually goes above that crankcase hose so that it's impossible to lift that AOS because that fuel(?) hose blocks the movement of that crankcase hose if I try to pull that AOS up - hmm... maybe tilting that towards the plenums would help... just playing with an idea.

Have you disconnected two coolant lines to the AOS?

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I have that big one disconnected. Those two small ones on top are still there because looks like I can remove the clamps after I have somehow tilted that AOS. At least the other one (probably both) are using a hose clamp and the screw side points towards the back of the engine.

There's now light at the end of the tunnel. Removed the bolts from AOS (as suggested and thx to De Jeeper) and now the thing is a bit more accessible. That weird small hose/wire that is connected to the fuel line is a major pain... because essentially it prevents from lifting or moving in general that AOS no more than an inch or so. If the crankcase hose would go over that whole thing could be lifted much more. Another thing that is a bit mystery is that I really can't pinch that crankcase breather connector properly because there's no room for a finger under the connector. It feels like a hard plastic that's part of the AOS itself. The new one doesn't have anything there so not sure what that is until I'm able to get that AOS removed. Now it will be just pure luck if I happen to put just enough force and place my fingers there to release the connector because I can pinch that lower part only from a side. Oh well, at least there's now hope - another thing is of course how to rebuild the thing. One thing that I'l try is to reroute that crankcase 90 angle connector above that wire from the fuel line.

Feeling victorious here - that miserable crankcase breather hose connector is now disconnected. It's getting late here so story continues tomorrow - AOS is still in place but all the major parts and obstacles are now removed. What might be more important is and based on this experience - removing that AOS is actually doable without lowering or dropping the engine - '99 Carrera 4 with Tiptronic. Not to mention that I'm a bit novice here.